Mutualism, commensalism and parasitism
The most common elements present in organic compounds are carbon, hydrogen, oxygen, and nitrogen.
➜ <u>Mendel conducted breeding experiments with garden peas</u>:
[i] He studied plants (pure) of a tall/short varities.
[ii] He crossed them and obtained F1 progeny.
[iii] He found that F1 progeny was all tall plants.
[iv] He selfed the (hybrid) plants if F1 progeny.
[v] He found that in F2 progeny there were tall as well as short plants.
[vi] The three quarter plants were tall and one quarter was short.
(or any other contrasting character may be taken).
<u>Note</u>: Here, F1 means <u>First fillial generation</u> and F2 means <u>Second fillial generation</u>.
